The instant invention relates to a vascular access guide or vein locator for patients requiring frequent and/or prolonged intravenous access for medical treatment. The method of locating and assuring proper access to a vein is also contemplated by the invention.
Many diseases require long-term continuous or intermittent intravenous therapy as a major part of their treatment including, but not limited to, such diseases as cancer, cystic fibrosis, renal disease, and major infections. During the last decade, many new intravenous access devices have been developed in order to administer the required medications into the patient's vein. However, problems associated with the insertion of these access devices and the trend to leave the devices indwelling in the vein for long periods of time (including times when they are not being used for drug and fluid administrations) can be dangerous to the patient.
One of the most frequently used methods for the insertion of an intravenous access device (catheter) is by percutaneous needle puncture directly into the vein with catheter insertion accomplished by an over the needle or through the needle technique. An over wire technique can also be used by inserting a guide wire through a needle, removing the needle, threading the access device or catheter into the vein using the wire as a guide and then removing the wire. In the past, it has been found that these methods could require several attempts to find an appropriate vein for catheter insertion. Every attempt to insert the catheter is associated with possible risks for major and possibly death-producing complications, such as pneumothorax, hemothorax, air embolism, vein or artery laceration and infections. It is obvious that by reducing the number of attempts for catheter insertion, one reduces accordingly the associated risks as mentioned. In addition to providing immediate access into the vein, due to its design with three-sided enclosure of the vein, the new vein locator would also reduce or eliminate some of the associated insertion risks such as pneumothorax induced by needle puncture of the lungs, and hemothorax induced by needle laceration of an artery or vein. Secondary to this would be the elimination or significant reduction of failed catheter insertions, with the implied risks of delaying critical and timely administration of intravenous medication to the patient. Moreover, the vein locator could significantly reduce the patient's pain and psychological trauma associated with difficult venous catheter insertion.
Following successful introduction of a percutaneously inserted venous catheter, the catheter customarily remains indwelling in the vein for the duration of the intravenous therapy, even if therapy is on an intermittent basis such as several days per month. The long-term indwelling catheter could also result in risks to the patient, including thrombus formation in or around the catheter, infection, phlebitis, air embolism, bleeding out of the catheter due to tubing or catheter breaks, and diminished quality of life due to the restraints of intensive maintenance care of the indwelling catheter.
Subcutaneously implanted vascular access portals with attached venous catheters are well known. However, their design involves a permanently attached, indwelling catheter, thus carrying the same inherent risks as mentioned for percutaneously inserted catheters. Another design is shown in U.S. Pat. No. 4,318,401 to Zimmerman. The portal of Zimmerman remains in the patient to receive catheters when required. A flange of the portal rests on or close to the outer skin surface of the patient. Thus, the portal would keep the skin of the patient available for the insertion of a catheter. Zimmerman's portal involves risks to the patient as: increased possibility of infection; permanently attached by sutures to the vein with difficult surgery involved for removal; and high accuracy required for fitting parts mechanically.